1. Field of the Invention
The present invention relates to a memory and a control unit.
2. Description of the Background Art
Generally, a user has demanded to reproduce music or image consecutively from a portion, at which previous reproduction has performed, in a power-up state, in an optical disk unit for reproducing music or image recorded in a CD, a DVD or the like. As a method for achieving such a demand, there is proposed a method of storing information showing the contents of a volatile memory holding data (data read from an optical disk and decoded) used in a subsequent power-up state and an internal state of a central processing unit such as a microcomputer in a nonvolatile memory in a power-down state before terminating the power-down state.
In the conventional method holding the data used in the subsequent power-up state in the power-down state, however, there are required an operation for reading the contents of the volatile memory once in the power-down state with the microcomputer and thereafter writing the same in the nonvolatile memory and an operation for writing the information showing the internal state of the microcomputer in the nonvolatile memory. Thus, control of the microcomputer is disadvantageously complicated.